Skew adjusting means for printing press impression roll

ABSTRACT

A web type printing press has a printing cylinder with an impression roll disposed thereabove to provide a nip through which the web passes. Idler rolls, one on each side of the nip, guide the web, tension it and effect its curvature around a portion of the impression roll. The axes of the printing cylinder, the idler rolls and the impression roll are normally parallel. Copy laydown skew adjustment means are provided to move the impression roll to change the angle between its axis and that of the printing cylinder to thereby alter the disposition of the web with respect to the surface of the printing cylinder. This adjustment means compensates for printing errors which would otherwise result from engraving or etching being improperly laid down (i.e., skewed) on the printing cylinder.

United States Patent 1191 Hardt Oct. 23, 1973 [54] SKEW ADJUSTING E N FPR NT 3,331,318 7/1967 Angnstyn 101/248 PRESS IMPRESSION ROLL 3,693,8559/1972 Bonner 226/21 [75] Inventor: David R. Hardt, Milwaukee, Wis.

[73] Assigneez Faustel, Inc., Butler, Wis.

[22] Filed: May 30, 1972 [21] Appl. No.: 257,765

52 US. Cl. 101/219, 101/248 ['51] Int. Cl. B41f 13/14, B4lf 13/24 [58]Field-of Search 101/248, 219;

[56] References Cited UNITED STATES PATENTS 2,256,801 9/1941 Barber101/248 2,265,457 12/1941 Stafford 101/219 2,276,465 3/1942 Clauberg....101/248 2,321,329 6/1943 Stafford..... 101/248 2,485,280 10/1949 Grace74/424.8 13 2,900,604 8/1959 Schmidt 74/424.8 B 3,167,968 2/1965Sandstrom. 74/4248 B 3,193,086 7/1965 Wilhelm 226/21 3,288,060 11/1966Miller 101/219 Primary Examiner-Robert E. Pulfrey AssistantExaminerWilliam Pieprz Att0rneyJames E. Nilles [57'] ABSTRACT A web typeprinting press has a printing cylinder with an impression roll disposedthereabove to provide a nip through which the web passes. Idler rolls,one on each side of the nip, guide the web, tension it and effect itscurvature around a portion of the impression roll. The axes of theprinting cylinder, the idler rolls and the impression roll are normallyparallel. Copy laydown skew adjustment means are provided to move theimpression roll to change the angle between its axis and that of theprinting cylinder to thereby alter the disposition of the web withrespect to the surface of the printing cylinder. This adjustment meanscompensates for printing errors which would otherwise result fromengraving or etching being improperly laid down (i.e., skewed) on theprinting cylinder.

9 Claims, 4 Drawing Figures PATENTEBUBT 2 3 I975 SHEET 2 BF 2 1; iii

SKEW ADJUSTING MEANS FOR PRINTING PRESS IMPRESSION ROLL BACKGROUND OFTHE INVENTION 1. Field of Use This invention relates generally to webprocessing machinery and particularly to means therein for correctlyadjusting the relationship between the web and processing means on acylinder therein for performing a repetitive process on the web.

2. Description of the Prior Art Some web processing machines employ arotating cylinder which has means thereon for performing a repetitiveprocess or function on a web. In a rotogravure printing press, forexample, the rotating cylinder takes the form of a printing cylinderwhich has engraving in the surface thereof which, when inked, actsagainst the web, which is backed by an irnpressionroll, to apply an inkpattern to the web. To insure correct disposition of the printed patternon the web, it is necessary that the web be correctly orientated withrespect to the printing cylinder and this is accomplished by idlerrollers located in fixed positions with respect to the printing cylinderwhichguide the web.- To insure correct disposition of the pattern on theweb, it is also necessary that engraving on the printing cylinder beproperly orientated with respect to the axis of the printing cylinder.Normally, the printing cylinder is engraved or etched by aphoto-chemical process wherein the cylinder is coated with aphoto-sensitive chemical, a photo- SUMMARY OF THE PRESENT INVENTION Inaccordance withthe present invention there is pro-- vided a webprocessing machine, such as a printing press, having an operating rollora cylinder therein, such as a printing cylinder, with operating 1means thereon, such as engraving, for performing a repetitive process orfunction, such as printing, on one side of a continuous web movingthrough the machine. A backup roll, such as an impression roll, isdisposed on the other side of the web and cooperates with the operatingroll to provide a nip between which'the web passes. Means are providedto guide the web, tension it and to cause it to follow the curvature ofa portion of the backup roll; Such means comprise idler rolls, one oneach side of the aforesaid nip. In a preferred embodiment, the axes ofthe operating roll, the idler rolls and, normally, the backup roll areparallel with each other. Skew adjustment means are provided in themachine to adjustably change the orientation of the web with respect tothe operating means on the cylinder in the event that such operatingmeans are improperly orientated on the cylinder to insure correctapplication of preferred embodiment of the invention, one end of thebackup roll is deflectably mounted on the machine frame and the otherend is adjustably movable in either direction in a plane which is normalto the common plane in which the axes of the operating roll and backuproll lie.

DRAWINGS FIG. 1 is an elevational view of a printing cylinder,impression roll and copy laydown skew adjustment means in a printingpress in accordance with the invention;

FIG. 2 is a view taken along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged view similar to FIG. 2 showing further details;and

FIG. 4 is a top plan view of a portion of the skew adjustment meanstaken along the line 4-4 of FIG. 3.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to FIG. 1, there isshown an elevational view of a portion of a rotogravure type printingpress having copy laydown skew adjustment means in accordance with thepresent invention. The printing press comprises a support frame havingspaced apart side plates 10 and 11 between which a supporting member orspacer in the form of a hollow box girder 12 is rigidly connected bybolts 13. Plate 10is on the drive side of the press and plate 1.1 is onthe operators side. The side plates 10 and ll are provided with rigidlyconnected inwardly extending brackets 13 and 14, respectively. A pair ofvertically disposed cylindrical guide pins 15 and 16 are connectedbetween box girder 12 and the brack-.

ets 13 and 14, respectively. The guide pins 15 and 16 afford support forhearing housings 17 and 18, respectively, which are mounted thereon andvertically movable or slidable with respect thereto. A main beam 19 isdisposed between the bearing housings l7 and 18. Idler arms 20 and 21are disposed between the ends of main beam 19 and the bearing housings17 and 18, respectively. Bolts 22 are employed to rigidly secure bearinghousing 17, idler arm 20 and one end of main beam 19 together and dowels23 assure rigidity and accurate alignment of idler arm 20 and main beam19. Vertical movement of the main beam is carried out by means ofactuators 31 which have their housings connected to the box girder 12and have downwardly extending movablerams 32 which are rigidly connectedto main beam 19. The bearing housing 18 and the idler in main beam 19and permit slight relative horizontal movement between the-end of mainbeam 19 and idler arm 21. A key 25 is disposed in horizontalv slots 26and 27 formed in the end of main beam 19 and in the inner surface ofidler arm 21 to insure accurate alignment during beam travel. Theshoulder screws 24 are provided with resilient washers 29 such asBelle-ville washers which tend to draw the end of main beam 19 and idlerarm 21 together but permit relative movement between the end of the mainbeam and the idler arm. Dowels 30 assure rigidity and accurate alignmentof idler arm 21 and bearing housing 18. Two manually operable threadedlockdown bolts 33are provided to rig idly secure the end of main beam 19to idler arm 21 when they are tightened. When loosened, they allowrelative movement between beam 19 and idler arm 21.

An impression roll 35 is mounted .for rotation on main beam 19 by meansof bearing blocks 36 which are secured by bolts 37 to the beam and isvertically movable therewith. A printing cylinder or roll 40 isrotatably mounted below the impression roll and is understood to besuitably supported in a fixed position on the press frame. As FIG. 2shows, idler members such as rollers 41 and'42 are connected between theidler arms and 21 near the extreme outerends of the idler arms and serveto guide, tension and effect curvature of a web 44 around a portion ofimpression roll 35. Web 44, which is to be printed, is threaded aroundidler roll 42, between the nip between impression roll and printingcylinder 40 and around idler roll 41. The web 44 is movable in thedirection of the arrow 46.

In a situation where the etching or engraving laid down on printingcylinder 40 (as by a photochemical etching process using a negative) iscorrectly disposed with respect to the axis of printing cylinder 40,then it is desired that the axis of impression roll 35, printingcylinder 40 and the axes of the idler rolls 41 and 42 would all beparallel to one another. Furthermore, all of these axes would be normalto the direction of movement of web 44. In a situation where the etchingor engraving on printing cylinder 40 is slightly skewed with respect tothe axis of the printing cylinder, as a result of incorrect negativeplacement during the etching process, it is necessary, in order toachieve correct placement of printing on web 44, to move the web veryslightly so that its direction of movement is normal to an imaginaryline on the surface of printing cylinder 40 which represents the trueaxial disposition of the etching or engraving on the printing cylinder.The means for accomplishing this in accordance with the presentinvention are hereinafter described.

-As FIGS. 3 and 4 show, relative movement between the end of main beam19 and idler'arm 21 is accomplished by means of a differential screw 46having an operating wheel 47, which screw has a first threaded portion48 which makes threaded engagement with a threaded hole 49 in a bracket50 which is rigidly secured to the end of main'beam 19 by a bolt 51.Screw 46 also has a second threaded portion 53 which makes threadedengagement with a threaded hole 54 in bearing housing 18. Thedifferential screw 46 is provided with operating wheel 47 which enablesit to be rotated inwardly or outwardly. The threads on portion 53 ofscrew 46 which engage the hole 54 bearing housing are different in pitchthan the threads on portion 48 which engage the hole 49 in bracket 50. Acompression type biasing spring 56 is disposed between housing 18 andbracket 50 to inhibit relative movement between those members andprevent rotation of screw 46. Therefore, when differential screw 46 isrotated clockwise with respect to FIG. 1, bracket 50 and the end of mainbeam 19 rigidly secured thereto are moved toward bearing housing 18.Conversely, counterclockwise movement of the differential screw resultsin bracket 50 and main beam 19 moving away from bearing housing 18. Theother end of the main beam is rigidly secured to idler arm 23 andhousing 18, but the beam is able to flex or deflect slightly to allowsuch movement. The differential screw 46 is provided with a calibrationdial which is rigidly secured to screw 46 and which, when moved withrespect to a dial pointer 57 ridigly secured to bracket 50, indicatesthe extent of movement of the end of main beam 19 with respect to idlerarm 21. In

I impression roll axis, printing cylinder axis and idler roll axes, areall parallel. However, when differential screw 46 is moved, the netresult is to cause the axis of impression roll 35 to pivot or deflect ina horizontal plane and to assume a non-parallel relationship with theaxes of the idler rolls 41 and 42 and printing cylinder 40. Thismovement causes web 44 to touch printing cylinder 40 in such a mannerthat there is a correct printing relationship between the etching orengraving on the printing cylinder surface and the surface of the webbeing printed.

RESUME A web processing machine, such as a printing press, has anoperating roll or a cylinder therein, such as printing cylinder 40, withoperating means thereon, such as engraving, for performing a repetitiveprocess or function, such as printing, on one side of a continuousweb 44moving through the machine. A backup roll, such as an impression roll35, is disposed on the other side of the web and cooperates withoperating roll 40 to provide a nip between which the web passes. Meansare provided to guide the web, tension it and to cause it to follow thecurvature of a portion of backup roll 35. Such means comprise idlerrolls, one on each side of the aforesaid nip. In a preferred embodiment,the axes of the operating roll 40, the idler rolls 41 and 42 and,normally, the backup roll 35 are parallel with each other. Skewadjustment means are provided in the machine to adjustably change theorientation of web 44 with respect to the engraving on cylinder 40 inthe event that such operating means are improperly orientated oncylinder 40 to insure correct application of such operation means totheweb. The skew adjustment means comprise a manually rotatabledifferential screw 46, which has one set of threads 48 which engage athreaded hole 49 in a bracket 50 rigidly secured to a. main beam 19which supports impression roll 35. Screw 46 has another set of threads53 (of different pitch than threads 48)'which engage a threaded hole 54in a bearing support 18 on the machine frame. The screw 46 of the skewadjustment means is adjustable to effect movement of backup roll 35 tochange the angle of the axis thereof with respect to the axis ofoperating roll 40 to change the disposition of web 44 with respect tothe operating roll. In a preferred embodiment, one end of backup roll 35is rigidly mounted on the machine frame and the other end is adjustablymovable in either direction in a plane which is normal to the commonplane in which the axes of operating roll 40 and backup roll 35 lie.Main beam 19 flexes or bends slightly to permit such adjustablemovement.

I claim:

1. In a web processing machine:

a support frame,

said frame having threaded means thereon,

an operating roll mounted for rotation on said frame,

a beam mounted on said frame,

one end of said beam being fixed with respect to said frame and theother end of said beam being movable,

said beam having threaded means thereon,

a backup roll mounted for rotation on said beam and cooperating withsaid operating roll to form a nip,

said rolls having axes which lie on a common plane,

at least one idler member mounted on said frame and having an axisparallel to the axis of said operating roll, i

and skew adjustment means including a rotatable threaded member locatedbetween said beam and said support frame for effecting deflectingmovement of said beam in a plane transverse to said common plane tochange the angle of the axis of said backup roll with respect'to theaxis of said operating roll, said rotatable threaded member includingfirst and second threaded portions of different screw pitch, said firstthreaded portion on said screw engaging the threaded means on said beamand said second threaded portion on said screw engaging the threadedmeans on said support frame.

2. A machine according to claim 1 which is a printing press, whereinsaid operating roll is a printing roll, and wherein said backup roll isan impression roll.

3. A press according to claim 2 wherein said idler member is an idlerroll.

4. A press according to claim 2 including at least a pair of idlermembers, one on each side of said nip formed by said printing roll andsaid backup roll.

one end of said beam being rigidly connected to said first bearinghousing,

said beam having threaded means thereon,

a first idler arm mounted at said one end of said beam,

a second idler arm located between said second bearing housing and theother end of said beam and rigidly connected to said second bearinghousing,

said other end of said beam being relatively deflectably movable withrespect to said one end of said beam,

at least one idler member connected between said first and second idlerarms on one side of said nip,

and skew adjustment means between said other end of said beam and saidsecond bearing housing to effect deflecting movement of said beam in aplane transverse to said common plane and with respect to said secondbearing housing, said skew adjustment means comprising a rotatablethreaded member engageable with said threaded means on said beam andwith said threaded means on said second bearing housing. 7

6. A machine according to claim 5 wherein said rotatable threaded memberincludes first and second threaded portions of different screw pitch andwherein said first portion engages said threaded means on said beam andwherein said second threaded portion en gages said threaded means onsaid second bearing housing.

7. A machine according to claim 6 including a guide key disposed inregistering slots provided in said other end of said main beam and insaid second idler arm.

8. A machine according to claim. 7 whereinrsaid idler arms support twoidler rolls, one roll being provided on each side of said nip.

9. A machine according to claim 8 wherein said machine is a printingpress, wherein said operating roll is a printing roll, and wherein saidbackup roll is an impression roll.

1. In a web processing machine: a support frame, said frame havingthreaded means thereon, an operating roll mounted for rotation on saidframe, a beam mounted on said frame, one end of said beam being fixedwith respect to said frame and the other end of said beam being movable,said beam having threaded means thereon, a backup roll mounted forrotation on said beam and cooperating with said operating roll to form anip, said rolls having axes which lie on a common plane, at least oneidler member mounted on said frame and having an axis parallel to theaxis of said operating roll, and skew adjustment means including arotatable threaded member located between said beam and said supportframe for effecting deflecting movement of said beam in a planetransverse to said common plane to change the angle of the axis of saidbackup roll with respect to the axis of said operating roll, saidrotatable threaded member including first and second threaded portionsof different screw pitch, said first threaded portion on said screwengaging the threaded means on said beam and said second threadedportion on said screw engaging the threaded means on said support frame.2. A machine according to claim 1 which is a printing press, whereinsaid operating roll is a printing roll, and wherein said backup roll isan impression roll.
 3. A press according to claim 2 wherein said idlermembEr is an idler roll.
 4. A press according to claim 2 including atleast a pair of idler members, one on each side of said nip formed bysaid printing roll and said backup roll.
 5. In a web processing machine:a support frame, an operating roll mounted for rotation on said frame,first and second spaced apart guide members on said frame, first andsecond bearing housings slidably mounted on said first and second guidemembers, respectively, said second bearing housing having threaded meansthereon, a beam located between said bearing housings and having arotatable backup roll mounted thereon cooperating with said operatingroll to provide a nip for said web, said rolls having axes lying in acommon plane, one end of said beam being rigidly connected to said firstbearing housing, said beam having threaded means thereon, a first idlerarm mounted at said one end of said beam, a second idler arm locatedbetween said second bearing housing and the other end of said beam andrigidly connected to said second bearing housing, said other end of saidbeam being relatively deflectably movable with respect to said one endof said beam, at least one idler member connected between said first andsecond idler arms on one side of said nip, and skew adjustment meansbetween said other end of said beam and said second bearing housing toeffect deflecting movement of said beam in a plane transverse to saidcommon plane and with respect to said second bearing housing, said skewadjustment means comprising a rotatable threaded member engageable withsaid threaded means on said beam and with said threaded means on saidsecond bearing housing.
 6. A machine according to claim 5 wherein saidrotatable threaded member includes first and second threaded portions ofdifferent screw pitch and wherein said first portion engages saidthreaded means on said beam and wherein said second threaded portionengages said threaded means on said second bearing housing.
 7. A machineaccording to claim 6 including a guide key disposed in registering slotsprovided in said other end of said main beam and in said second idlerarm.
 8. A machine according to claim 7 wherein said idler arms supporttwo idler rolls, one roll being provided on each side of said nip.
 9. Amachine according to claim 8 wherein said machine is a printing press,wherein said operating roll is a printing roll, and wherein said backuproll is an impression roll.